He's already been through this scenario, with one difference: Roos was the highly drafted rookie in 2005.
Roos learned from veteran Brad Hopkins while playing right tackle for a season before taking over that position for the next eight years. Now Roos is busy teaching Taylor Lewan, the No. 11 pick overall, while trying to hold him off with one year left on his own contract.
''It was going to happen eventually,'' Roos said. ''You can't play forever. So at some point somebody's going to come in. It doesn't matter who you are. There's a younger kid at some point who's either going to push you or just replace you. It was bound to happen at some point.
''We'll see if I can hold him off.''
The 6-foot-7 Roos has been in the starting lineup since being drafted him in the second round out of Eastern Washington in 2005. He even started his first NFL game at left tackle before swinging to right tackle the rest of his rookie season. Hopkins retired, and Roos moved to left tackle where he has started 128 of his 143 games missing only once in 2012 due to an appendectomy.
Only four men have started more games on the offensive line for this franchise than Roos, and two of those are in the Hall of Fame in Bruce Matthews and former head coach Mike Munchak. Roos is poised to pass Benji Olsen (152) and could tie Munchak with 159 games by starting every game this season.
Roos, 31, has only one year left on his current contract. He said offensive line coach Bob Bostad called when the Titans drafted Lewan out of Michigan as the third left tackle selected and told him that the veteran was their guy at left tackle.
''I'm here for one more year as far as I know,'' Roos said. ''And I've been blocking the blind side for nine years, and I'll do that for one more year. If there's more, there's more. If not, I'll find out what else I'm doing. Until I'm told otherwise, I'm here.''
Lewan, also 6-7, said he feels more comfortable at left tackle where he's played his entire career. He credits Roos with helping him on details setting up for pass protection or when run blocking. But the rookie wants to play as soon as possible.
''No one likes riding the bench,'' Lewan said.
The Titans also have another veteran at tackle in Michael Oher, signed to a four-year deal in March. Oher has played all 80 games in his first five seasons, not counting 10 playoff games. Tennessee signed Oher to replace David Stewart at right tackle.
Right now, Lewan is practicing in the team's organized team activities that started Tuesday at both left and right tackle backing up Roos and Oher. Coach Ken Whisenhunt has said Lewan will start if the rookie earns that right. Asked how Roos and Oher are handling the addition of Lewan, Whisenhunt noted both are veterans.
''That's what this league's all about,'' Whisenhunt said. ''It's about competition. So they've been very good pros. They've worked hard, done everything we've asked of them and I'm excited about both those guys.''
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